/*数据合法性检验函数*/

/*测试输入数据是否为空*/
var blankRE=/^\s*$/;

function checkEmpty(text) {
	if (blankRE.test(text)) {
		return true;
	} else {
		return false;
	}
}

/* 日期合法性检验 MM/DD/YYYY */

/**
 * DHTML date validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
 */
// Declaring valid date character, minimum year and maximum year
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function isInteger(s){
	var i;
	if (s.length == 0) return false;
    for (i = 0; i < s.length; i++){   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag){
	var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
	for (var i = 1; i <= n; i++) {
		this[i] = 31;
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30;}
		if (i==2) {this[i] = 29;}
   } 
   return this;
}

function isDate(dtStr){
	var daysInMonth = DaysArray(12);
	var pos1=dtStr.indexOf(dtCh);
	var pos2=dtStr.indexOf(dtCh,pos1+1);
	var strMonth=dtStr.substring(0,pos1);
	var strDay=dtStr.substring(pos1+1,pos2);
	var strYear=dtStr.substring(pos2+1);
	strYr=strYear;
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1);
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1);
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1);
	}
	month=parseInt(strMonth);
	day=parseInt(strDay);
	year=parseInt(strYr);
	if (pos1==-1 || pos2==-1){
		//alert("The date format should be : mm/dd/yyyy")
		return false;
	}
	if (strMonth.length<1 || month<1 || month>12){
		//alert("Please enter a valid month")
		return false;
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		//alert("Please enter a valid day")
		return false;
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		//alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false;
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		//alert("Please enter a valid date")
		return false;
	}
	return true;
}
function compareDate(date1, date2) {
	var ilegal = 2;
	var res = 0;
	
	if (isDate(date1) == false || isDate(date2) == false) {
		//alert("Invalidate date.");
		return ilegal;
	} else {
		var month1 = parseInt(date1.substring(0, 2), 10);
		var day1 = parseInt(date1.substring(3, 5), 10);
		var year1 = parseInt(date1.substring(6, 10), 10);
		var month2 = parseInt(date2.substring(0, 2), 10);
		var day2 = parseInt(date2.substring(3, 5), 10);
		var year2 = parseInt(date2.substring(6, 10), 10);
		var d1 = new Date(year1, month1, day1);
		var d2 = new Date(year2, month2, day2);
		
		if (d1.getTime() - d2.getTime() < 0) {
			res = -1;
		} else if (d1.getTime() - d2.getTime() > 0) {
			res = 1;
		}
		return res;
	}
}

